I believe datacoin was the first project that was aiming for storing your files in the blockchain to allow decentral cloud storage. (correct me if I'm wrong)
The only problem were the guys behind datacoin. They never managed to get it to the next level.
Storj looks very professional and looks way better. I'll be watching this closely.
You're not wrong, though technically Bitcoin and Namecoin could also be used to store data in the blockchain if you knew how to. Not sure if they can accommodate actual files though.
But yeah, I was thinking Datacoin too. It was an innovative coin and yet it died. The dev disappeared and there were also issues with the blockchain becoming too bloated. I think it was supposed to grow by about 500GB a year. It would be interesting to see what these new guys will do differently.